How does oxygen get to deep ocean bottoms?

Oxygen reaches deep ocean bottoms primarily through a process called thermohaline circulation, where surface waters cool, become denser, and sink. Additionally, oxygen enters the deep ocean through wind-driven mixing and the sinking of oxygen-rich water masses from polar regions. Some oxygen is also supplied by the decay of organic matter that sinks from the surface, which can lead to localized areas of low oxygen in the deep sea. Overall, these processes ensure that oxygen is distributed throughout the ocean's depths, although levels can vary significantly.